1. Field of the Invention
The present invention relates to a cogeneration system in which waste heat of a drive source adapted to drive a generator is used in a heat pump type air conditioner, and, more particularly, to a cogeneration system which includes a waste-heat-supplied heat exchanger to heat a refrigerant, using waste heat of a drive source, during a heating operation of a heat pump type air conditioner.
2. Description of the Related Art
FIG. 1 is a schematic view illustrating a conventional cogeneration system.
As shown in FIG. 1, the conventional cogeneration system includes a generator 2 to generate electricity, a drive source 10, which operates to drive the generator 2, and generates waste heat during the operation thereof, such as an engine (hereinafter, the drive source 10 will be referred to as an “engine”), a waste heat recoverer 20 to recover waste heat generated from the engine 10, and a heat consumer 30 to use the waste heat recovered by the waste heat recoverer 20, such as a thermal storage tank.
The electricity generated from the generator 2 is supplied to various electric home appliances including the heat pump type air conditioner 4 and various home illumination devices.
The generator 2 and engine 10 are disposed in an engine room E defined in a chassis (not shown), which is constructed separately from the heat consumer 30.
The heat pump type air conditioner 4 includes compressors 5, a 4-way valve 6, indoor heat exchangers 7, expansion devices 8, and outdoor heat exchangers 9.
When the heat pump type air conditioner operates in a cooling mode, each compressor 5 compresses a refrigerant introduced thereinto. The compressed refrigerant passes through the 4-way valve 6, outdoor heat exchangers 9, expansion devices 8, indoor heat exchangers 7, and 4-way valve 6, in this order, and returns to the compressors 5. In this case, each outdoor heat exchanger 9 functions as a condenser, and each indoor heat exchanger 7 functions as an evaporator to absorb heat from indoor air.
On the other hand, when the heat pump type air conditioner operates in a heating mode, the refrigerant compressed in each compressor 5 passes through the 4-way valve 6, indoor heat exchangers 7, expansion devices 8, outdoor heat exchangers 9, and 4-way valve 6, in this order, and returns to the compressors 9. In this case, each outdoor heat exchanger 9 functions as an evaporator, and each indoor heat exchanger 7 functions as a condenser to heat indoor air.
The waste heat recoverer 20 includes an exhaust gas heat exchanger 22 to absorb heat from exhaust gas discharged from the engine 10, and a cooling water heat exchanger 24 to absorb heat from cooling water used to cool the engine 10.
The exhaust gas heat exchanger 22 is connected with the heat consumer 30 via a first heat supply line 23. Accordingly, the exhaust gas heat exchanger 22 can transfer the waste heat absorbed from the exhaust gas of the engine 10 to the heat consumer 30 via the first heat supply line 23. As mentioned above, the heat consumer 30 may be a thermal storage tank.
The cooling water heat exchanger 24 is connected with the heat consumer 30 via a second heat supply line 24. Accordingly, the cooling water heat exchanger 24 can transfer the waste heat absorbed from the cooling water of the engine 10 to the heat consumer 30 via the second heat supply line 24.
In the above-mentioned conventional cogeneration system, however, the waste heat of the engine 10 is used only in the heat consumer 30, without being used in the heat pump type air conditioner 4. As a result, it is impossible to obtain maximal system efficiency.